Revolving door operating mechanism and speed controller



Oct. 31-, 1967 E. SHECKELLS 3,349,876

REVOLVING DOOR OPERATING MECHANISM AND SPEED CONTROLLER Filed March 1967 5 Sheets-Sheet 1 N INVENTOR 2 AMUEL E. SHECKELLS u.

ATTORNEY REVOLVING DOOR OPERATING MECHANISM AND SPEED CONTROLLER Filed March a, 1967 5 Sheets-Sheet 2 ATTORNEY Oct. 31, 1967 A. E. SHECKELLS 3,349,876

REVOLVING DOOR OPERATING MECHANISM AND SPEED CONTROLLER- 3 Sheets-Sheet 5 Filed March 6, 1967 INVENTOR \AMUEL E. SHECKELLS ATTORNEY United States Patent 3,349,876 REVOLVING DOOR OPERATING MECHANISM AND SPEED CONTROLLER Amuel E. Sheckells, Evansville, Ind., assignor to International Steel Company, Evansville, Ind., a corporation of Indiana Filed Mar. 6, 1967, Ser. No. 620,998 8 Claims. (Cl. 188-185) ABSTRACT OF THE DISCLOSURE A revolving door operating mechanism having a motor drive and clutch assembly operatively connected to a speed control mechanism including a centrifugal brake assembly which governs the speed of rotation of the revolving door shaft, and a pump operatively connected to the centrifugal brake assembly for supplying lubricating fluid thereto.

Cross-references to related applicati ns This application is a continuation-in-part of application S.N. 523,222, filed Jan. 26, 1966, now US, Patent 3,308,912, dated Mar. 14, 1967, which, in turn, is a continuation in-part of application S.N. 382,791, filed July 15, 1964, now US. Patent 3,307,660, dated Mar. 7. 1967.

Background of the invention The invention of the present application relates to an operating mechanism for a revolving door, and more particularly, to a motor drive and clutch assembly operatively connected to a speed control mechanism of the type disclosed in my afore-mentioned copending application S.N. 382,791, filed July 15, 1964, now U. S. Patent 3,307,660, dated Mar. 7, 1967, wherein a gear train is positioned within a housing and operatively connected be tween the revolving door shaft and a centrifugal brake assembly; a pump being operatively connected to the centrifugal brake assembly for supplying a volume of oil to the speed control mechanism which not only provides continuous lubrication of the mechanism but also coacts with the braking assembly to provide a smooth and dependable braking action; the housing, gear train, brake mechanism and oil pump being constructed and arranged to form a low profile assembly.

As mentioned in my copending application S.N. 523,222,; filed Jan. 26, 1966, now US. Patent 3,308,912, dated Mar. 14, 1967, when using revolving doors in the entrances of buildings constructed in accordance with todays architectural designs, it is necessary that the design of the speed control device and operating mechanism be architecturally consistent with the building. Accordingly, the revolving door operating mechanism and speed control device must have a relatively thin, low profile to render the assembly readily adaptable for selective mounting in either overhead or floor-type installations. In order to maintain thislow-profile characteristic, the clutch assembly, employed in the door operating mechani sm as disclosed in my copending application S.N. 523,222, filed Jan. 26, 1966, now US. Patent 3,308,912, dated Mar. 14, 1967, is positioned concentrically within the centrifugal brake assembly of the door speed controller.

Summary In the continuing research and experimentation with my prior operating mechanism and speed controllers to improve their operating capabilities, while at the same time maintaining the low-profile characteristics, the operating mechanism and speed controller of the present invention has been devised wherein the flexible drive shaft of the motor is connected to the centrifugal brake assembly by means of a Torrington roller clutch bearing assembly mounted on the shaft of the centrifugal brake assembly. By mounting the clutch assembly on the centrifugal brake shaft, rather than concentrically within the centrifugal brake assembly as disclosed in my aforementioned copending application, a greater mass may be imparted to the spring biased brake shoes to thereby increase the braking action of the assembly.

The centrifugal brake shoes employed in the assembly of the present invention are also provided With gauges correlated with the biasing force of the brake shoe springs so that the biasing force of the springs may be quickly and accurately varied depending upon the selected r.p.n1. of the door shaft at which it is desired that the brake shoes are to be actuated.

The worm gear employed for driving the centrifugal brake assembly shaft is provided with a Torrington roller clutch adapted to slidably receive the endof the flexible drive shaft, whereby a quick-disconnect coupling is provided to thereby facilitate the disassembling of the motor drive from the operating mechanism during maintenance of the assembly.

The pump for supplying lubricating fluid to the centrifthe gear train housing and cooperates with the centrifugal brake shaft for pumping the lubricating fluid to the brake housing. By positioning the pump on the bottom wall of the gear train housing, rather than on the shaft of the centrifugal brake assembly, as disclosed in my aforementioned pending applications, a smaller volume of lubricating fluid is required; thus, the fluid level in the gear train housing is lowered to a point below the aperture formed in the housing side wall through which the flexible drive shaft extends. By maintaining the fluid level below this aperture, leakage of the fluid from the housing is substantially prevented.

Brief description of the drawings FIGURE 1 is a top plan view of the improved revolving door operatingmechanism and speed control assembly with the cover plate removed therefrom;

FIGURE 2 is an enlarged, fragmentary, taken substantially along line 22 of FIG. 1;

FIGURE 3 is a fragmentary sectional view taken along line 3-3 of FIG. 2;

FIGURE 4 is an exploded, perspective view of the lubricating fluid pump and showing its relationship to the bottom Wall of the gear train housing;

FIGURE 5 is a fragmentary sectional view taken substantially along line 55 of FIG. 2;

FIGURE 6 is a sectional view taken along line 6-6 of FIG. 5; and,

FIGURE 7 is a top plan view of the bottom wall of the centrifugal brake housing.

Description of the .preferred embodiment sectional view a motor 1 having a flexible drive shaft 2 operatively connected to a Torrington roller clutch bearing assembly 3 mounted on the shaft 4 of a centrifugal brake assembly 5. The flexible drive shaft is enclosed by a tubular conduit 6 having one end connected to the motor housing and the opposite end threadably secured within an aperture formed in the end wall of a cast housing 7.

An overhead-type revolving door installation is illustrated in FIGS. 1 and 2, wherein the upper end of the revolving door shaft (not shown) is adapted to extend upwardly through a suitable seal 8 positioned within an opening 7a formed in the bottom wall of housing 7. The end of the door shaft is adapted to be threadably secured to a key member 9 which is splined to the hub 10 of the gear train main gear 11 which is rotatably mounted within the housing by means of an anti-friction bearing 12. The main gear meshes with a pinion 13 carried by a shaft 14 which is rotatably mounted within the housing by means of bearings 15. An intermediate gear 16 is also carried by shaft 14 and meshes with a pinion 17 carried by a second shaft 18 which is rotatably mounted within the housing by means of bearings 19. A helical gear 20 is carried by shaft 18 and meshes with a smaller helical gear 21 integrally formed on the lower end of the centrifugal brake assembly shaft 4 which is rotatably mounted within the housing by means of bearing 22.

As will be seen in FIGS. 2, 3 and 7, the centrifugal brake assembly comprises a housing 23 positioned within housing 7 by means of dowel pins 24 and secured therein by suitable bolts 25. The centrifugal brake assembly shaft 4 extends upwardly through the bottom wall of the brake housing 23 and has a rotor 26 keyed as at 27 to the upper end portion thereof. The rotor is provided with a pair of parallel bores 26a which extend through the rotor and are disposed on opposite sides of a tapped bore 261) which extends through the rotor in the medial portion thereof. The bores 26a are provided with guide pins 28 which project outwardly from each side of the rotor and slidably receive a pair of oppositely disposed arcuate brake shoes 29 having brake bands 29a secured to the eripheral surface thereof. Each shoe is held on its respective pair of guide pins by means of a bolt 30 positioned within a recess 2% formed in the brake shoe and threaded into the tapped bore 26b, the brake shoes being urged radially inwardly by means of coil springs 31 positioned between the bolt heads and a shoulder 290 formed on the inner end of recess 29a. By this construction and arrangement, the centrifugal force produced by rotation of shaft 4 causes the brake shoes 29 to slide radially whereby the brake bands 29a engage the peripheral wall 23a of the brake housing to thereby control the speed of the mechanism. As the brake shoes move radially outwardly the springs 31 are compressed so that when the rotational speed of shaft 4 is decreased to the point where the biasing force of the springs overcomes the centrifugal force of the rotating shaft and associated rotor, the springs expand thereby biasing the brake shoes inwardly to their inoperative position.

The biasing force of springs 31 may be varied by moving bolts 30 inwardly or outwardly relative to the rotor, the bolts being held in adjusted position by means of suitable set screws 32 extending normal to the bolts. One of the features of the present invention is the provision of a gauge for the centrifugal brake assembly whereby the biasing force of springs 31 may be quickly and accurately accomplished to thereby cause the brake shoes to be actuated at a selected r.p.m. of the revolving door shaft. To this end, as will be seen in FIGS. 2 and 3, a pair of slots 29d are formed in the top wall of the brake shoes, each slot communicating with a respective recess 2%, and being in alignment with the bolt head 30. The top wall of the brake shoe adjacent the peripheral edge of each slot is provided with a scale 33 graduated in terms of the rpm. of the revolving door shaft, for purposes of illustration, the scale shown in FIG. 3 being graduated from 9 to 11 rpm.

When it is desired to vary the biasing force of the spring 31, the set screws 32 are loosened and the bolts 31 are then threaded into or out of the rotor until the bottom face of each bolt head is aligned with selected graduation on the peripheral edge of the slots. For instance, if it is desired to have the centrifugal brake shoes become actuated when the revolving door reaches 9 rpm. the bolts are adjusted until the bottom faces thereof are aligned with 9 on the scale, For a delayed actuation of the brake shoes, that is, for actuation of the brake shoes when the revolving door reaches 10 or 11 rpm, the bolts would be threaded slightly further into the rotor thereby compressing the springs thus increasing their radial inward biasing force. After the adjustment of the bolts is made the set screws 32 are once again tightened to hold the bolts in the adjusted position.

In order to provide continuous lubrication and to enhance the smooth operation of the door speed control mechanism, the housing 7 is provided with a volume of oil the level of which is indicated by dashed lines in FIG. 2. The oil is in communication with one end of a cylindrical recess 4a formed in the lower end portion of the shaft 4, the opposite end of the cylindrical recess communicating with a longitudinal bore 4b formed in the upper portion of the shaft. A pump assembly 34 is positioned within the cylindrical recess 4a for feeding the lubricating oil through bore 4b into the centrifugal brake housing. As will be seen in FIG. 4, the pump assembly comprises a cylindrical plug 34a having a helical groove formed on the outer peripheral surface thereof. A tab 34b is secured to the lower end of the cylindrical plug and is adapted to be inserted within a recess 7b formed in the bottom wall of the housing, whereby the cylindrical plug is held stationary with respect to the housing 7. The recess 7b extends radially outwardly beyond the portion of the bottom wall of the housing in which the bearing 22 is seated, and then upwardly to the upper surface of the bottom wall of the housing to form a port through which the oil flows into the cylindrical recess 4a.

From the above description of the pump assembly it will be readily seen that when the centrifugal brake assembly shaft 4 is rotated relative to the cylindrical plug 34a the oil contained in recess 4a will be pumped upwardly through bore 4b and onto the upper surface of the brake shoes 29 whereby the centrifugal force generated by the rotating shoes causes the oil to be flung radially outwardly thereby forming a thin film of oil on the brake housing wall 23a thus, insuring a smooth braking action when the brake bands 29a engage the brake housing wall 23a. As will be seen in FIG. 7, the bottom wall of the brake housing is provided with a plurality of ports 35 to allow the oil to gravitate from the brake housing back into housing 7.

The positioning of the pump assembly on the lower end of the centrifugal brake shaft is another important feature of the present invention since by this construction and arrangement the oil level within housing 7 is maintained well below the aperture in the housing wall through which the tubular conduit 6 extends; thus, leakage of the oil from the housing is substantially prevented.

As will be seen in FIGS. 5 and 6, the operative connectrons between the flexible drive shaft 2 and the Torrington roller clutch bearing assembly carried by the centrifugal brake assembly shaft 4, comprises, a worm gear 36 mounted within a housing 37 secured to the lower surface of the brake housing bottom wall (FIG. 2) by means of bolts 37a. Suitable bearings 38 are provided on each end of the worm gear for rotatably mounting the gear within the housing, and a Torrington roller clutch bearing assembly 39 is mounted concentrically within the worm gear and is adapted to slidably receive the end of the flexible shaft, which is tapered as at 2a to facilitate the insertion thereof through the clutch assembly. By this construction and arrangement a quick-disconnect coupling is provided to thereby facilitate the disassembling of the motor drive from the operating mechanism during maintenance of the mechanism. Worm gear 36 is adapted to mesh with another worm gear 40 rotatably mounted within housing 37 by means of bearings 41. The Torrington roller clutch bearing assembly 3 is mounted concentrically within worm gear 40, whereby when the motor 1 is energized the flexible drive shaft is rotated to drive worm gear 36 which in turn drives worm gear 40.

In the normal operationof the revolving door operating mechanism and speed controller, a person desiring to pass through an entrancewa within which the revolving door is mounted, enters the door enclosure in the usual manner, and by pushing on the revolving door closes a suitable switch means connected to an electrical circuit to energize the motor to thereby drive the shaft 4 which in turn simultaneously drives the centrifugal brake assembly 5 and gear train connected to the revolving door shaft. If the user wishes to pass through the door at a rate faster than the door is driven by the motor through the Torrington roller clutch bearing assembly 3, pushing on the door Wing will cause the gear train and shaft 4 to rotate at a greater rate in the same direction and cause shaft 4 to rotate relative to the Torrington roller clutch bearing assembly 3. The increased rotation rate of shaft 4 overrides the rotation of worm gear 40 and the clutch bearing assembly and thus allows faster rotation of the door, which rotation rate is limited by the setting of the centrifugal brake assembly 5.

The motor employed in the operating mechanism of the present invention is a 2%" diameter, .22 H.P., DC motor and, through suitable electrical control means, is adapted to be energized through an operating range of 0 to 12 rpm. of the revolving door shaft. For anstance, the motor can be energized to rotate from O r.p.m. to a selected high speed, then to a selected lower speed and back to 0 rpm. to stop the door at a predetermined position, or, if desired, sufiicient voltage can be fed to the motor to maintain a slight torque on the revolving door shaft while maintaining the door at 0 rpm. until being used, whereupon, the voltage to the motor is increased causing the motor to rotate at a higher speed to increase the torque of the revolving door shaft, thereby rotating the door.

What is claimed is:

1. A revolving door operating mechanism and speed control device of the character described comprising, a housing, a main gear rotatably mounted within said housing, said main gear being adapted to be secured to the revolving door shaft, centrifugal brake means positioned Within the housing, a shaft having one end connected to said centrifugal brake means, gear train means rotatably mounted within the housing, said gear train means being operatively connected between the main gear and the opposite end of said shaft, a roller clutch bearing assembly mounted on said shaft concentrically therewith and intermediate the ends thereof, and motor means operatively connected to said clutch assembly, whereby upon energization of said motor means, the clutch assembly is rotated together with said shaft to cause rotation of said centrifugal brake means while simultaneously rotating the rovolving door shaft through the gear train; said main gear, gear train means, centrifugal brake means and clutch assembly, all being positioned within said housing in spaced, parallel, closely adjacent horizontal planes to thereby form a low-profile operating mechanism and speed control device adapted for selective installation in either an overhead or floor-type revolving door installation.

2. A revolving door operating mechanism and speed control device according to claim 1, wherein a second housing is mounted within the first-mentioned housing, the centrifugal brake means being positioned within said second housing, a volume of lubricating fluid contained nism during maintenance of the within said first-mentioned housing, and pump means for feeding oil from the first housing into said second housing.

3. A revolving door operating mechanism and speed control device according to claim 2, wherein the pump means comprises, a recess formed in said opposite end of the shaft, said recess being in communication with the volume of fluid contained in the first housing, a cylindrical plug having a helical groove formed on the peripheral surface thereof, said plug being positioned within said recess and secured to the first housing, a longitudinal bore formed concentrically within the shaft communicating at one end with the recess and at the opposite end with the centrifugal brake means, whereby upon rotation of the shaft relative to the cylindrical plug lubricating fluid is pumped from the recess through the bore onto the centrifugal brake assembly.

4. A revolving door operating mechanism and speed control device according to claim 1, wherein the motor means for driving the clutch assembly comprises, a motor, gear means connected to said clutch assembly, and a drive shaft connected between said motor and said gear means.

5. A revolving door operating mechanism and speed control device according to claim 4, wherein the gear means includes a worm gear, a roller clutch bearing assembly mounted concentrically within said worm gear, the end of said drive shaft being slidably received within the worm gear clutch assembly, whereby a quick-disconnect coupling is provided to thereby facilitate the disassemblying of the motor drive from the operating mechamechanism.

6. A centrifugal brake assembly for use in a revolving door speed control device of the type having a gear train operatively connected between the main gear of the revolving door shaft and the centrifugal brake assembly, said centrifugal brake assembly comprising, a housing, a rotatable shaft extending through said housing, one end of said shaft being connected to said gear train means, a rotor secured to the opposite end of said shaft, a pair of opposed bolts secured to said rotor and extending radially outwardly therefrom, a brake shoe slidably mounted on each bolt and adapted to engage the wall of the housing, spring means positioned between each brake shoe and the head of its respective bolt for biasing the brake shoe radially inwardly toward the rotor, said bolts being radially movable relative to the rotor for varying the biasing force of the spring means, and gauge means carried by the brake shoes and correlated with the biasing force of the brake shoe springs, whereby the biasing force of the springs may be quickly and accurately varied depending upon the selected r.p.m. of the door shaft at which it is desired that the brake shoes are to be actuated.

7. A centrifugal brake assembly according to claim 6 wherein the bolts and associated spring means are positioned within recesses formed in the brake shoes, said gauge means comprising a pair of slots formed in the top wall of the brake shoes, each slot communicating with a respective recesss and being in alignment with the bolt head, and a scale graduated in terms of r.p.m. of the revolving door shaft provided on the top wall of the brake shoe adjacent the peripheral edge of each slot, whereby when varying the biasing force of the springs the bolt heads are aligned with selected graduati ons on the scale.

8. A revolving door speed control device comprising, a housing, a main gear rotatably mounted within said housing and adapted to be connected to the revolving door shaft, a second housing mounted within the first-mentioned housing, centrifugal brake means positioned within the second housing, a shaft having one end connected to said centrifugal brake means, gear train means rotatably mounted within the first-mentioned housing, said gear train means being operatively connected between the main gear and the opposite end of said shaft, a volume of lubricating fluid contained within said first-mentioned housing, and pump means for feeding oil from the first housing into said second housing, said pump means comprising a recess formed in said opposite end of the shaft, said recess being in communication with the volume of lubricating fluid contained in the first housing, a cylindrical plug having a helical groove formed on the peripheral surface thereof, said plug being positioned within the recess, concentrically thereto and secured to the first housing, a longitudinal bore formed concentrically within the shaft communicating at one end with the recess and at the opposite end with the centrifugal brake means, whereby upon rotation of the shaft relative to the cylindrical plug lubricating fluid is pumped from the recess through the bore onto the centrifugal brake assembly.

References Cited UNITED STATES PATENTS 2,128,531 8/1938 Hagenbook 49-43 10 DUANE A. REGER, Primary Examiner. 

1. A REVOLVING DOOR OPERATING MECHANISM AND SPEED CONTROL DEVICE OF THE CHARACTER DESCRIBED COMPRISING, A HOUSING A MAIN GEAR ROTATABLY MOUNTED WITHIN SAID HOUSING, SAID MAIN GEAR BEING ADAPTED TO BE SECURED TO THE REVOLVING DOOR SHAFT, CENTRIFUGAL BRAKE MEANS POSITIONED WITHIN THE HOUSING, A SHAFT HAVING ONE END CONNECTED TO SAID CENTRIFUGAL BRAKE MEANS, GEAR TRAIN MEANS ROTATABLY MOUNTED WITHIN THE HOUSING, SAID GEAR TRAIN MEANS BEING OPERATIVELY CONNECTED BETWEEN THE MAIN GEAR AND THE OPPOSITE END OF SAID SHAFT, A ROLLER CLUTCH BEARING ASSEMBLY MOUNTED ON SAID SHAFT CONCENTRICALLY THEREWITH AND INTERMEDIATE THE ENDS THEREOF, AND MOTOR MEANS OPEAATIVELY CONNECTED TO SAID CLUTCH ASSEMBLY, WHEREBY UPON ENERGIZATION OF SAID MOTOR MEANS, THE CLUTCH ASSEMBLY IS ROTATED TOGETHER WITH SAID SHAFT TO CAUSE ROTATION OF SAID CENTRIFUGAL BRAKE MEANS WHILE SIMULTANEOUSLY ROTATING THE ROVOLVING DOOR SHAFT THROUGH THE GEAR TRAIN; SAID MAIN GEAR, GEAR TRAIN MEANS, CENTRIFUGAL BRAKE MEANS AND CLUTCH ASSEMBLY, ALL BEING POSITIONED WITHIN SAID HOUSING IN SPACED, PARALLEL, CLOSELY ADJACENT HORIZONTAL PLANES TO THEREBY FORM A LOW-PROFILE OPERATING MECHANISM AND SPEED CONTROL DEVICE ADAPTED FOR SELECTIVELY INSTALLATION IN EITHER AN OVERHEAD OR FLOOR-TYPE REVOLVING DOOR INSTALLATION. 